Effect of biofuel waste, urea, deer browsing and vegetation control on Pinus banksiana seedling growth on a dry upland site in central Canada

Author(s):  
John Herbert Markham ◽  
Jon Makar

Ash from biofuels and nitrogen fertilizer are increasingly being used as soil amendments. While this can increase tree growth, it can also increase mammalian grazing and competition with vegetation. We applied moderate amounts (1.5 t ha<sup>-1</sup> y<sup>-1</sup>) of ash and 74 kg N ha<sup>-1</sup> y<sup>-1</sup> of urea in each of two years to a well-drained site in southeastern Manitoba, planted with <i>Pinus banksiana</i>. Subplots received deer browsing and/or vegetation control. The ash resulted in an increase in pH in the upper 15m of mineral soil from ca. 5.7 to 6.6, and the urea created short-term spikes in soil inorganic N (NH<sub>4</sub> and NO<sub>3</sub>) levels. Urea combined with ash significantly increased seedling relative growth rates in the first two years, with seedlings being largest with urea, with or without ash. However, by the fourth year seedling growth and size did not differ between the amendments. Urea application increased browsing damage to 91 %, but only when vegetation was mowed. Browsing guards resulted in seedlings having 1.6 times greater shoot mass by the end of the fourth growing season. These results suggest that on sandy soils in the dry region of central Canada, <i>P. banksiana</i> may get little benefit from ash applications.

2021 ◽  
Vol 14 (1) ◽  
pp. 34-40
Author(s):  
KK Suzuki ◽  
Y Watanabe ◽  
T Kubota ◽  
Y Kuwano ◽  
Y Kawauchi ◽  
...  

1991 ◽  
Vol 71 (4) ◽  
pp. 397-410 ◽  
Author(s):  
X. J. Xiao ◽  
D. W. Anderson ◽  
J. R. Bettany

Pedogenesis and its effect on calcium (Ca), magnesium (Mg) and phosphorus (P) was studied on a sequence of seven Gray Luvisol soils in central Saskatchewan. The soils were formed on calcareous glacial till under trembling aspen (Populus tremuloides Michx), mixedwood (aspen and white spruce) (Picea glauca (Moench) Voss)) and coniferous (black spruce and jack pine) (Picea mariana (Mill) BSP and Pinus banksiana Lamb) forests. Soils under aspen had the highest concentration of total and exchangeable Ca and Mg in litter layers and Ae horizons, and had Ae and Bt horizons that were least acidic. The most acidic Ae and Bt horizons and lowest amounts of Ca and Mg occurred under coniferous forests, whereas the soils under mixedwood stands were intermediate. The thickness of eluvial (Ae and AB) horizons increased along the aspen to coniferous sequence. All soils had about 40% less P in their A and B horizons than was calculated to have been present at the start of soil formation. The greatest decrease in P was observed in the thickest and most acidic soil under coniferous forest. The present litter layers and vegetation make up only a small proportion of the P removed from the mineral soil. Unusually large amounts of P appear to have been translocated from A and B horizons during development of Gray Luvisols, in comparison to Chernozemic or even Podzolic soils. Our hypothesis proposes that P is ineffectively retained in the solum as P-clay-humus, or iron-P complexes and that organic P moves along with the soil water, laterally and downslope through permeable Ae horizon over less permeable Bt horizons, or vertically through macropores. Key words: Boreal forest, nutrient cycling, phosphorus losses, weathering, soil formation


1993 ◽  
Vol 23 (10) ◽  
pp. 2101-2109 ◽  
Author(s):  
Timo Kuuluvainen ◽  
Timo J. Hokkanen ◽  
Erkki Järvinen ◽  
Timo Pukkala

The spatial structure of vegetation and soil properties of a patchy Scots pine (Pinussylvestris L.) forest of 1 ha was described and examined in relation to the height growth of pine seedlings in the understory. Measured ecosystem properties included the distribution and sizes of canopy trees, within-stand radiation regime, composition of understory vegetation, and topsoil and mineral soil properties. The joint distance dependent effects of large trees were described as the influence potential, derived from the ecological field theory approach. The variation in understory vegetation and soil characteristics was described as score values, derived from multivariate analyses, summarizing the variation of multiple measured variables; factor analysis was used for topsoil and mineral soil properties and canonical correspondence analysis was used for understory species composition. The spatial variation of variables was examined and mapped using geostatistical techniques. The influence potential of canopy trees, as determined by their size and spatial distribution, correlated most strongly with seedling growth, so that the height growth of seedlings was retarded in the vicinity of trees. Correlations suggest that canopy trees also affected seedlings indirectly through their dominating effect on the properties of understory vegetation and humus layer. The mineral soil nutrient content showed a weak positive correlation with seedling height growth. All the factors related to seedling growth showed substantial small-scale variation across the 1-ha study site. The analysis suggests that the variation in seedling height growth in the understory of the studied Scots pine stand is largely caused by the spatial heterogeneity of both above- and below-ground factors and by the joint effect of their complex interaction.


1996 ◽  
Vol 74 (3) ◽  
pp. 383-390 ◽  
Author(s):  
John Hoddinott ◽  
Rickey Scott

Plant growth responds to light quality, as evaluated by the red/far-red (R/FR) quantum flux ratio, and to the level of CO2. Pinus banksiana, Picea mariana and Picea glauca seedlings were raised at 350, 700, or 1050 μL∙L−1 CO2 and high or low R/FR ratios and growth was measured over a 16-week growth period. Far-red rich light enhanced the whole plant and height relative growth rates of Pinus banksiana. The three species showed species specific responses in plant organ relative growth rates and partitioning ratios. On the basis of their biomass partitioning the species would be ranked Pinus banksiana < Picea mariana < Picea glauca for shade tolerance. In commercial operations, seedlings grown for outplanting are selected, in part, on the basis of plant form as described by the stem height/diameter ratio. More desirable ratios were obtained at ambient CO2 concentrations for Pinus banksiana and Picea mariana in red rich light and for Picea glauca in far-red rich light. Keywords: seedling growth, light quality, CO2 enrichment.


1988 ◽  
Vol 4 (2) ◽  
pp. 185-198 ◽  
Author(s):  
W. H. O. Ernst ◽  
T. Tietema ◽  
E. M. Veenendaal ◽  
R. Masene

ABSTRACTDormancy and germination ecology of two Harpagophytum species (Pedaliaceae) from an open Acacia savanna in Botswana were investigated. The maintenance of dormancy is governed partly by the seed coat but mainly by the endosperm and the embryo itself, as demonstrated by removal of the endosperm. Dissemination of the seed from the fruit can be delayed for several years without affecting the viability of the embryo, due to very low respiration rates.Germination can be enhanced slightly by high temperatures under natural conditions, and by gibberellic acid or removal of the endosperm under laboratory conditions. Relative growth rates for both Harpagophytum species are lower than for subtropical grasses and legumes, due to a strong investment in root and tuber biomass. Germination and seedling growth is discussed in relation to the drought avoidance syndrome and the animal disperser syndrome.


2000 ◽  
Vol 30 (6) ◽  
pp. 845-854 ◽  
Author(s):  
Masahiro Shishido ◽  
Christopher P Chanway

Seeds of two hybrid spruce (Picea glauca (Moench) Voss × Picea engelmannii Parry ex Engelm.) ecotypes were inoculated with one of six plant growth-promoting rhizobacteria (PGPR) strains previously shown to be able to stimulate spruce growth in controlled environments. The resulting seedlings were grown in the greenhouse for 17 weeks before outplanting at four reforestation sites. Inoculation with five of the six strains caused significant seedling growth promotion in the greenhouse, which necessitated analysis of relative growth rates (RGR) to evaluate seedling performance in the field. Four months after outplanting, most strains enhanced spruce shoot or root RGRs in the field, but seedling growth responses were strain specific. For example, Pseudomonas strain Ss2-RN significantly increased both shoot and root RGRs by 10-234% at all sites, but increases of 28-70% were most common. In contrast, Bacillus strain S20-R was ineffective at all outplanting sites. In addition, seedlings inoculated with four of the six strains had significantly less shoot injury than control seedlings at all sites. Evaluation of root colonization by PGPR indicated that bacterial population declines were not related to spruce growth response variability in the field. Our results indicate that once plant growth promotion is induced in the greenhouse, seedling RGR can increase by more than 100% during the first growing season in the field. However RGR increases of 21-47% were more common and may be more representative of the magnitude of biomass increases that can result from PGPR inoculation.


2020 ◽  
Author(s):  
Florin Pendea ◽  
◽  
Nandakumar Kanavillil ◽  
Sreekumari Kurissery ◽  
Ben Longstaff

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