Effects of logging residue harvest in thinnings on amounts of soil carbon and nutrients in Scots pine and Norway spruce stands

To study growth responses to refertilization, 12 Scots pine (Pinus sylvestris L.) and 6 Norway spruce (Picea abies (L.) Karst.) stands used in long-term nitrogen (N) fertilization experiments were refertilized with N, either alone or with various combinations and doses of phosphorus (P), potassium (K), and magnesium (Mg). Many of the experimental plots had previously been subjected to heavy N fertilization regimes over a period of 2030 years. On average, for all the experiments, the latest N addition resulted in a significant growth increase, corresponding to 57% of the mean annual volume increment and comparable with the response to the initial fertilization. Differences in growth response between fertilization with N alone or in combination with PKMg were in most cases insignificant for both tree species. Overall, the joint addition of PKMg resulted in a nonsignificant additional growth increase of 0.2 m3·ha1·year1, corresponding to 6% of the N fertilization effect. Repeated additions of N alone had no effect on the P, K, and Mg concentrations in current-year needles. It was concluded that the repeated N fertilizations did not cause any serious nutrient deficiencies.

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Validating the predicted saw log and pulpwood proportions and gross value of Scots pine and Norway spruce harvest at stand level by Most Similar Neighbour analyses and a stem quality database

Silva Fennica ◽

10.14214/sf.9972 ◽

2018 ◽

Vol 52 (4) ◽

Cited By ~ 1

Author(s):

Jukka Malinen ◽

Harri Kilpeläinen ◽

Erkki Verkasalo

Keyword(s):

Norway Spruce ◽

Scots Pine ◽

External Quality ◽

Log Reduction ◽

Unit Value ◽

Stem Quality ◽

Spruce Stands ◽

Average Unit ◽

Wood Procurement ◽

Tree Quality

Detailed pre-harvest information about the volumes and properties of growing stocks is needed for increased precision in wood procurement planning for just-in-time wood deliveries by cut-to-length (CTL) harvesters. In the study, the non-parametric Most Similar Neighbour (MSN) methodology was evaluated for predicting external quality of Scots pine and Norway spruce, expressed as stem sections fulfilling the saw log dimension and quality requirements of Finnish forest industry, as they affect the recovery of timber assortments and the value of a pre-harvest stand. Effects of external tree quality were evaluated using saw log recovery and saw log reduction caused by stem defects, as well as total timber value (â¬) and average unit value (â¬ m) in a stand. Root mean square error (RMSE) of saw log recovery and reduction were 9.12 percentile points (pp) for Scots pine and 6.38 pp for Norway spruce stands. In the unit value considerations, the predictions compared with measurements resulted in the RMSE of 3.50 â¬ m and the bias of 0.58 â¬ m in Scots pine stands and 2.60 â¬ m, and 0.35 â¬ m in Norway spruce stands, respectively. The presented MSN based approach together with the utilization of the external stem quality database included in the ARVO software could provide dimension and external quality predictions usable for pre-harvest assessment of timber stock at a stand level. This prediction methodology is usable especially in analyses where timber assortment recoveries, values and unit prices are compared when different bucking objectives are used.â3â3â3â3â3

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Radial growth of Scots pine and Norway spruce stands as an indicator of soil and environmental conditions

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/875/1/012074 ◽

2021 ◽

Vol 875 (1) ◽

pp. 012074

Author(s):

B Aparin ◽

B Babikov ◽

D Zolotukhin ◽

E Mingareeva

Keyword(s):

Norway Spruce ◽

Tree Ring ◽

Scots Pine ◽

Radial Growth ◽

Ring Width ◽

Tree Ring Width ◽

Average Growth ◽

Cyclical Pattern ◽

Spruce Stands ◽

Successive Change

Abstract The study presents an analysis of radial growth of Scots pine and Norway spruce trees growing on drained soils formed on varved clays at the sample sites of the Lisino Experimental Forestry (Lisino). Based on dendrochronological studies in Lisino, it has been found that the radial growth of Scots pine and Norway spruce is a sensitive indicator of changes in the soil water regime, climate, and phytocenotic relationships. On the basis of the character of tree-ring width growth, the growth charts allowed distinguishing zones with close to average growth values, as well as with increased and decreased values of radial growth. The cyclical pattern of tree ring width is well expressed in the successive change of zones. The availability of dendrochronological research materials with precise spatial and temporal reference makes it possible to organize monitoring of radial growth of trees as an indicator of changes in climate and habitat conditions.

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