Aboveground biomass responses to organic matter removal, soil compaction, and competing vegetation control on 20-year mixed conifer plantations in California

We examined fifth-year seedling response to soil disturbance and vegetation control at 42 experimental locations representing 25 replicated studies within the North American Long-Term Soil Productivity (LTSP) program. These studies share a common experimental design while encompassing a wide range of climate, site conditions, and forest types. Whole-tree harvest had limited effects on planted seedling performance compared with the effects of stem-only harvest (the control); slight increases in survival were usually offset by decreases in growth. Forest-floor removal improved seedling survival and increased growth in Mediterranean climates, but reduced growth on productive, nutrient-limited, warmhumid sites. Soil compaction with intact forest floors usually benefited conifer survival and growth, regardless of climate or species. Compaction combined with forest-floor removal generally increased survival, had limited effects on individual tree growth, and increased stand growth in Mediterranean climates. Vegetation control benefited seedling growth in all treatments, particularly on more productive sites, but did not affect survival or alter the relative impact of organic matter removal and compaction on growth. Organic matter removal increased aspen coppice densities and, as with compaction, reduced aspen growth.

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Effects of organic matter removal, soil compaction and vegetation control on 10th year biomass and foliar nutrition: LTSP continent-wide comparisons

Forest Ecology and Management ◽

10.1016/j.foreco.2012.04.014 ◽

2012 ◽

Vol 278 ◽

pp. 35-54 ◽

Cited By ~ 79

Author(s):

Felix Ponder ◽

Robert L. Fleming ◽

Shannon Berch ◽

Matt D. Busse ◽

John D. Elioff ◽

...

Keyword(s):

Organic Matter ◽

Soil Compaction ◽

Foliar Nutrition ◽

Organic Matter Removal ◽

Vegetation Control

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Aspen and white spruce productivity is reduced by organic matter removal and soil compaction

The Forestry Chronicle ◽

10.5558/tfc2012-058 ◽

2012 ◽

Vol 88 (03) ◽

pp. 306-316 ◽

Cited By ~ 13

Author(s):

Richard Kabzems

Keyword(s):

Organic Matter ◽

Soil Properties ◽

Bulk Density ◽

Soil Compaction ◽

Forest Floor ◽

Mineral Soil ◽

White Spruce ◽

Soil Bulk Density ◽

Post Treatment ◽

Organic Matter Removal

Declines in forest productivity have been linked to losses of organic matter and soil porosity. To assess how removal of organic matter and soil compaction affect short-term ecosystem dynamics, pre-treatment and year 1, 5 and 10 post-treatment soil properties and post-treatment plant community responses were examined in a boreal trembling aspen (Populus tremuloidesMichx.)-dominated ecosystem in northeastern British Columbia. The experiment used a completely randomized design with three levels of organic matter removal (tree stems only; stems and slash; stems, slash and forest floor) and three levels of soil compaction (none, intermediate [2-cm impression], heavy [5-cm impression]). Removal of the forest floor initially stimulated aspen regeneration and significantly reduced height growth of aspen (198 cm compared to 472–480 cm) as well as white spruce (Picea glauca [Moench] Voss) height (82 cm compared to 154–156 cm). The compaction treatments had no effect on aspen regeneration density. At Year 10, heights of both aspen and white spruce were negatively correlated with upper mineral soil bulk density and were lowest on forest floor + whole tree removal treatments. Recovery of soil properties was occurring in the 0 cm to 2 cm layer of mineral soil. Bulk density values for the 0 cm to 10 cm depth remained above 86% of the maximum bulk density for the site, a soil condition where reduced tree growth can be expected.

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Soil properties and aspen development five years after compaction and forest floor removal

Canadian Journal of Soil Science ◽

10.4141/s97-026 ◽

1998 ◽

Vol 78 (1) ◽

pp. 51-58 ◽

Cited By ~ 40

Author(s):

Douglas M. Stone ◽

John D. Elioff

Keyword(s):

Organic Matter ◽

Soil Properties ◽

Populus Tremuloides ◽

Soil Compaction ◽

Forest Floor ◽

Forest Type ◽

Woody Species ◽

Stand Development ◽

Site Productivity ◽

Organic Matter Removal

Forest management activities that decrease soil porosity and remove organic matter have been associated with declines in site productivity. In the northern Lake States region, research is in progress in the aspen (Populus tremuloides Michx. and P. grandidentata Michx.) forest type to determine effects of soil compaction and organic matter removal on soil properties and growth of aspen suckers, associated woody species, herbaceous vegetation, and on stand development. Four treatments: (1) total tree harvest (TTH); (2) TTH plus soil compaction (CPT); (3) TTH plus forest floor removal (FFR); and (4) TTH plus CPT + FFR were applied after winter-harvest of a 70-yr-old aspen stand growing on a loamy sand with a site index(age50) of 20.7 m. The CPT treatment significantly increased bulk density and soil strength of the surface 30 cm of soil and neither have recovered during the 5 yr since treatment. The CPT plots had 19.6 thousand (k) suckers ha−1, less than half that of the TTH and FFR treatments; mean diameter (19.4 mm) and height (271 cm) were greatest on the TTH plots. The disturbance treatments (CPT, FFR, and CPT + FFR) each reduced biomass of foliage, stems, and total suckers compared with the TTH treatment. Total aboveground biomass (herbs + shrubs + suckers) was less than half that of TTH plots. There were 5.0 k saplings (suckers >2.5 cm DBH) ha−1 on the TTH plots, but fewer than 1.0 k ha−1 in the other treatments. The disturbance treatments decreased 5-yr growth of potential crop trees, delayed early stand development, and temporarily reduced stockability and site productivity of an aspen ecosystem. Key words: Soil compaction, organic matter removal, site productivity, stand development

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EFFECT OF SOIL COMPACTION AND ORGANIC MATTER REMOVAL ON GENOTYPIC DIVERSITY, GENETIC STRUCTURE, AND TRAIT EXPRESSIONS IN ASPEN

10.37099/mtu.dc.etdr/146 ◽

2016 ◽

Author(s):

Mehmet Acet

Keyword(s):

Organic Matter ◽

Genetic Structure ◽

Soil Compaction ◽

Genotypic Diversity ◽

Organic Matter Removal

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Nitrogen mineralization dynamics following the establishment of a loblolly pine plantation

Canadian Journal of Forest Research ◽

10.1139/x02-184 ◽

2003 ◽

Vol 33 (2) ◽

pp. 364-374 ◽

Cited By ~ 60

Author(s):

Qingchao Li ◽

H Lee Allen ◽

Carlos A Wilson

Keyword(s):

Organic Matter ◽

Loblolly Pine ◽

Soil Type ◽

N Mineralization ◽

The United States ◽

Net N Mineralization ◽

Soil Core ◽

Organic C ◽

Organic Matter Removal ◽

Vegetation Control

The USDA Forest Service initiated a national study in the early 1990s to examine the effects of organic matter removal, compaction, and vegetation control on tree growth and soil processes at several locations across the United States and Canada. Our study was undertaken on the Lower Coastal Plain of North Carolina installation during the second and the fifth growing seasons following loblolly pine (Pinus taeda L.) plantation establishment. We used the in situ soil core incubation method to assess net N mineralization, and collections were conducted monthly from March to December in 1993 and 1996. The largest differences in N mineralization resulted from soil type differences between blocks. Organic matter removal did not affect N mineralization in either year; however, compaction reduced N mineralization during both years. Vegetation control had a pronounced positive effect on N mineralization and was only slightly less important as compared with soil type. Mineralization rates in year 5 were 80% less than in year 2. We hypothesized that the high N mineralization rates in year 2 may be related to a decrease in the input of soluble organic C following harvest (reducing immobilization), a quick mineralization of microbial N, fluctuating soil temperature and water conditions, and fine roots and litter biomass input following harvest.

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Aspen plant community response to organic matter removal and soil compaction

Canadian Journal of Forest Research ◽

10.1139/x05-133 ◽

2005 ◽

Vol 35 (8) ◽

pp. 2030-2044 ◽

Cited By ~ 15

Author(s):

Sybille Haeussler ◽

Richard Kabzems

Keyword(s):

Organic Matter ◽

Species Diversity ◽

Plant Community ◽

Populus Tremuloides ◽

Soil Compaction ◽

Forest Floor ◽

Community Response ◽

Organic Matter Removal ◽

Soil Aeration ◽

Year Effect

Organic matter removal and reduced soil aeration porosity during logging are important factors influencing the sustained productivity of managed forest ecosystems. We studied the 4-year effect of these factors on diversity and composition of a trembling aspen (Populus tremuloides Michx.) plant community in northeastern British Columbia, Canada, in a completely randomized experiment with three levels of organic matter removal (tree stems; stems and slash; stems, slash, and forest floor) and three levels of soil compaction (none; intermediate (2-cm impression); heavy (5-cm impression)). Tree stem removal caused the greatest change in species diversity (30% of variance; ANOVA p ≤ 0.01), increasing the dominance of aspen and Calamagrostis canadensis (Michx.) Beauv. over other species. Slash removal had little effect. Forest floor removal caused the greatest compositional change (37% of variance; MANOVA p = 0.001), favoring ruderal over bud-banking species. Presence or absence of forest floor better explained these changes than any soil physical or chemical parameter. Although dominance of aspen over Calamagrostis was positively correlated with soil aeration porosity (R2 = 0.50, n = 27, p < 0.001), there were few differences between intermediate and heavy compaction. In this ecosystem, disturbances that reduce forest floor thickness without compacting soils will likely optimize plant species diversity and enhance aspen regrowth.

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Nine-Year Response of Hardwood Understory to Organic Matter Removal and Soil Compaction

Northern Journal of Applied Forestry ◽

10.1093/njaf/25.1.25 ◽

2008 ◽

Vol 25 (1) ◽

pp. 25-31 ◽

Cited By ~ 4

Author(s):

Felix Ponder

Keyword(s):

Organic Matter ◽

Weed Control ◽

Soil Compaction ◽

Understory Vegetation ◽

Soil Productivity ◽

Organic Matter Removal ◽

Woody Vines ◽

Plant Groups ◽

Whole Tree ◽

Measurement Period

Abstract The effects of three levels of organic matter removal (OMR) and three levels of soil compaction (SC) on the development of understory vegetation in a central hardwood forest were evaluated 9 years after treatments were applied as part of a national program of long-term soil productivityresearch. The three levels of biomass removal (OMR) were removal of merchantable boles only (OM0), removal of the whole tree (OM1), and removal of the whole tree plus forest floor (OM2). The three levels of soil compaction (SC) were none (C0), medium (C2), and severe (C2). Weeds were controlledin all plots for the first 2 years. Understory vegetation within 81 7.9-m2 subplots was inventoried by species and quantified into plant groups of woody (trees, shrubs, and woody vines) and herbaceous (annuals, perennials, and grasses) at year 5 (after 3 years of no weed control)and year 9 (after 7 years of no weed control). Vegetation was analyzed for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg). OMR did not significantly affect the overall number of plants over the 5-year measurement period, but there were differences for both woodyvines and grasses, which were highest in the OM0 treatment in 1999, but by 2003, they were not different. There were no differences in plant numbers among plant groups for SC in the 1999 measurement period between treatments for any plant group, but there were significantly fewer trees andwoody vines in the C2 treatments than in the C0 or C1 treatments in 2003; the opposite was true for herbaceous annuals, which were highest in C1 and C2 treatments. Over the 5-year measurement period, only the height of woody vines was significantly affected by OMR, but SC significantly affectedthe height of all plant groups over the 5-year measurement period. Annually, however, trees were tallest in the OM0 and C0 treatment than in OM2 and C2 treatments. The annual height of other plants, excluding trees, was affected only 1 year of 5 by OMR. Fewer trees and shorter trees in thesevere compaction treatment suggest that, in the short term, soil productivity has been affected on the site.

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