Research Interests: Geography, Environmental Science, Agroforestry, Ecology, Wetland, and 4 moreHabitat, Swamp, Boreal, and Taiga
Abstract Soil sustainability is key to maintaining forest growth and ecosystem services around the world. Determining how to maintain soil functions and knowing when soils are degraded can be difficult. Complicating our understanding of... more
Abstract Soil sustainability is key to maintaining forest growth and ecosystem services around the world. Determining how to maintain soil functions and knowing when soils are degraded can be difficult. Complicating our understanding of the relationship between soil functions and soil sustainability is the inherent heterogeneity of forest soils. However, maintaining or improving soil organic matter (OM) contents is essential to soil health, quality, and sustainability, and both OM quantity and quality have key roles in soil porosity, water infiltration, gas exchange, nutrient cycling, aggregate stability, trafficability, and flood control. Forest management practices, such as harvesting and site preparation, have a major impact on soil properties, which can vary widely across different soil types and climatic regimes. We also examine how compaction, fertilization, and herbicide use can influence forest sustainability. This chapter is structured to give an overview of management-related changes on soil properties, and how these practices may be refined to sustain or improve forest soil quality and productivity. In addition, a synthesis of soil monitoring practices is provided to show the importance of this information for adaptive management.
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... Management on Wetland Functions in a Sub-Boreal Swamp CC Trettin, MF Jurgensen, JW McLaughlin, and MR Gale CONTENTS Introduction 411 ... Minnesota, and Wisconsin Note: Estimates are based on Forest Inventory and Analysis cover-types... more
... Management on Wetland Functions in a Sub-Boreal Swamp CC Trettin, MF Jurgensen, JW McLaughlin, and MR Gale CONTENTS Introduction 411 ... Minnesota, and Wisconsin Note: Estimates are based on Forest Inventory and Analysis cover-types (Smith and Hahn, 1987, 1989 ...
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Forest harvesting and regeneration may cause changes in soil and solution chemistry that adversely affect environmental quality. Organic C content in the forest floor and mineral soil, and dissolved organic carbon (DOC) fractions in the... more
Forest harvesting and regeneration may cause changes in soil and solution chemistry that adversely affect environmental quality. Organic C content in the forest floor and mineral soil, and dissolved organic carbon (DOC) fractions in the soil solution and groundwater were investigated in a black spruce [Picea mariana (Miller) BSP] swamp 5 yr after the application of two silvicultural prescriptions: whole‐tree harvest only and whole‐tree harvest followed by site preparation bedding. Soil organic carbon (SOC) content in the forest floor of both treatments were significantly lower than that of an uncut control stand. However, SOC in the upper 50 cm of mineral soil of the bedded treatment was similar to that of the control, while both were about 20% higher than SOC in the harvest‐only treatment. Total DOC concentrations ranged from 12 to 87 mg/L in the soil solution and 6 to 46 mg/L in the groundwater and did not differ among treatments. Hydrophobic acids were the dominant DOC fraction across all treatments, but the proportion of hydrophobic strong acids increased at the expense of hydrophilic acids in the harvest‐only treatment. Carboxyl content of hydrophilic acids in the soil water was 7.0 mmol/g hydrophilic compound in the control stand and 4.4 mmol/g in the treatments. Hydrophobic acid carboxyl content across treatments was 4.6 mmol/g hydrophobic substance. Relative to C loss and changes in water chemistry, these results indicate that 5 yr after whole‐tree harvesting, this forest site has not yet fully equilibrated.
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Research Interests: Environmental Science, Agronomy, Forestry, Forest Ecology, Biological Sciences, and 15 moreEnvironmental Sciences, Forest Management, Nitrogen, Cost effectiveness, Planting, Rocky Mountains, Seedling survival, Container, Forest Floor, Organic Matter, Overall Survival, Lodgepole Pine, Pinus Contorta, Growing Season, and Height Growth
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Wetlands are characterized by water at or near the soil surface for all or significant part of the year, are a source for food, fiber and water to society, and because of their position in landscapes and ecological structure help to... more
Wetlands are characterized by water at or near the soil surface for all or significant part of the year, are a source for food, fiber and water to society, and because of their position in landscapes and ecological structure help to moderate floods. They are also unique ecosystems with long-persistent flora and fauna. Because water is a driving factor for existence as a wetland, these systems are particularly vulnerable to climate change, especially as warming is accompanied by changes the quality and quantity of water moving through these systems. Because they are such diverse ecosystems, wetlands respond differently to stressors and, therefore, require different management and restoration techniques. In this chapter we consider forested wetland soils, their soil types, functions, and associated responses to climate change. Wetland processes are not well understood and therefore additional information is needed on these areas. In addition, more knowledge is needed on the interface ...
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A 5-year-old plantation of Eucalyptus. nitens Maid. grew over 4 m in height and added basal area of 4.6 m2/ha in 12 months. Production of dry matter in the above-ground portion of the stand averaged 36 tonnes/ha/annum over a 2-year period... more
A 5-year-old plantation of Eucalyptus. nitens Maid. grew over 4 m in height and added basal area of 4.6 m2/ha in 12 months. Production of dry matter in the above-ground portion of the stand averaged 36 tonnes/ha/annum over a 2-year period with over 70% in bole material. The season of sampling was unimportant in determining the biomass of stand components since foliage production was closely linked with leaf litterfall. Branch and stem mass increased with time as woody litterfall was small compared with production. Nutrient concentrations in living tissue tended to decrease with increased tree size and often varied among seasons. Although season of sampling affected estimates of stand nutrient content, no simple pattern of change was observed. Calorific values of foliage and live branches were highest in summer or autumn but seasonal differences in stem components were not statistically significant.
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Decay and fire play interactive roles in recycling wood and other organic materials in forest ecosystems~ and contribute to the development of high quality soils in the Northern Rocky Mountains . Decayed wood~ charcoal~ and other... more
Decay and fire play interactive roles in recycling wood and other organic materials in forest ecosystems~ and contribute to the development of high quality soils in the Northern Rocky Mountains . Decayed wood~ charcoal~ and other decomposed organic matter are the principal media for ectomycorrhizal and nonsymbiotic nitrogen fixing microbes . The activities of these microbes are critical to the growth of forest trees . The balance between decay and fire~ as it affects the amount~ distribution~ and type of organic matter~ controls the ability of forest soils to support the growth of trees .
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Trembling aspen is a fast growing, broadly distributed tree in North America that reproduces by root suckers (clonally) and by seeds (sexually). Since timber harvesting can affect both reproduction pathways by changing the soil... more
Trembling aspen is a fast growing, broadly distributed tree in North America that reproduces by root suckers (clonally) and by seeds (sexually). Since timber harvesting can affect both reproduction pathways by changing the soil properties, we assessed genet diversity, genetic structure, and phenotypic trait expression of trembling aspen populations after clear-cut harvesting in a long-term soil productivity study site in Michigan. A total of 323 stems in replicated plots having heavy soil compaction and surface organic matter (OM) removed, and the untreated controls, were analyzed at microsatellites and for phenotypic traits. Overall, higher spatial aggregation of ramets from the same genet, a greater spatial separation of different genets, and a very good phenotypic separation among genets was observed in the treatment plots. In contrast, for plots with spatially intermixed clones phenotypic separation was much lower. Genetic differentiation was high between individual plots, but s...
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Key messageClonal delineation at nuclear microsatellites and phenotypic traits showed high correspondence and revealed an important role of both sexual and clonal reproduction for stand genetic structure.AbstractQuaking aspen (Populus... more
Key messageClonal delineation at nuclear microsatellites and phenotypic traits showed high correspondence and revealed an important role of both sexual and clonal reproduction for stand genetic structure.AbstractQuaking aspen (Populus tremuloides Michx.) grows throughout the northern and central portions of North America. Reproduction occurs both sexually via seeds and clonally from root suckers. Clonal delineation using morphological/phenological traits, and more recently, highly variable nuclear microsatellites have shown considerable variation in the size of clonal assemblies, and the relative importance of sexual versus clonal reproduction across the species range. In order to provide reliable estimates of genet size (N/G; ramets per sampled genet) and genotypic diversity (G/N; genets/ramets), and to compare genetic and phenotypic clone delineation, we characterized 181 sampled stems (ramets) at seven nuclear microsatellites, and morphological and phenological traits from six clones (genet size ≥11). Genotypic diversity was moderate (G/N = 0.18) and within the range reported in other studies across North America. Multivariate statistics revealed a high correspondence between genetic and phenotypic clone delineation, both with and without predefined genetic groups (94.2 %, 81.7 %). Moderate average genet size (5.6 ramets per genet) and the occurrence of genetically distinct single-ramet genets surrounded by larger genets suggested intermediate levels of sexual reproduction contributing to the genetic structure of this stand. Significant differences among genets were found for phenological and morphological traits such as bark thickness and leaf shape. However, most clones showed no significant differences in diameter growth which was likely caused by poor drainage in this high clay soil that inhibited the expression of genetic differences in growth.
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ABSTRACT
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The effects of burning no nitrogen (N) losses and transformations in red pine (Pinus resinosa Ait.), eastern hemlock [Tsuga canadensis (L.) Carr.], and Douglas‐fir (Pseulotsuga menziesii)/western larch (Larix occidentalis Nutt.) forest... more
The effects of burning no nitrogen (N) losses and transformations in red pine (Pinus resinosa Ait.), eastern hemlock [Tsuga canadensis (L.) Carr.], and Douglas‐fir (Pseulotsuga menziesii)/western larch (Larix occidentalis Nutt.) forest floor were investigated. Organic horizon samples were burned at 400°C for 30 min in a top‐heating oven to simulate field conditions. Measurements taken immediately after burning showed total and available N losses from the O1 horizons but gains in total and available N in underlying layers. After burning, the litter was incubated for 5 weeks and analyzed for ammonium and nitrate concentrations and changes in acidity. Each forest floor type displayed varying patterns of ammonification, nitrification and immobilization of N. The N changes appeared related to the differing initial N contents of the organic material.
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Three northern hardwood stands were clearcut to evaluate the effect of whole tree harvesting on sites of varying quality. Stands were growing on sandy, outwash soils and had red maple (Acer rubrum L.) site indices of 15, 19, and 20 and... more
Three northern hardwood stands were clearcut to evaluate the effect of whole tree harvesting on sites of varying quality. Stands were growing on sandy, outwash soils and had red maple (Acer rubrum L.) site indices of 15, 19, and 20 and biomass values of 114, 165, and 181 Mg ha−1. Harvesting did not alter extractable soil P levels significantly on any site. Forest floor weights decreased to similar values on all sites 1.5 yr after harvest. Nitrogen losses of over 1.3 Mg ha−1 occurred in the top meter of soil on all sites. This was attributed to the mixing of the forest floor with the surface mineral soil by the full tree skidding and the subsequent leaching of mineralized N. Soil exchangeable K decreased more than 1 Mg ha−1 on all sites. Changes in Ca and Mg were much smaller on the low and medium than on the high site. These losses from surface soil horizons are higher than reported previously for clearcutting northern hardwoods on till soils. The greatest impact of whole tree harve...
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... year rotation. Survival of interplanted black locust was very poor due to susceptibility to frost. The potential ... surviving individuals. A provenance trial of 20 seed sources showed variability in frost resistance among seed... more
... year rotation. Survival of interplanted black locust was very poor due to susceptibility to frost. The potential ... surviving individuals. A provenance trial of 20 seed sources showed variability in frost resistance among seed sources. Data is ...
Research Interests: Environmental Science, Phosphorus, Seasonality, Solvent Extraction, Plant growth, and 15 moreSite index, North America, Locust, Thermal Stability, Moisture Content, Short rotation forestry, Maple, Specific Gravity, Sugar Maple, Chemical Composition, Forest Floor, Forest Growth, Experimental Data, Data Extraction, and Physical Properties
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Abstract Organic matter (OM) is an integral part of site productivity for a forest, and understanding the effects of OM removal on various forms of carbon (C) cycling is important for land managers and for policy makers. In this study, we... more
Abstract Organic matter (OM) is an integral part of site productivity for a forest, and understanding the effects of OM removal on various forms of carbon (C) cycling is important for land managers and for policy makers. In this study, we utilized the Lake States Long-Term Soil Productivity (LTSP) study sites, located along a gradient in soil texture (clay, silt loam and sand) and high to low productivity, to evaluate the impacts of two OM removal treatments on belowground wood decomposition. In 2013, approximately 20 years after the LTSP treatments had been installed, we placed standardized aspen and loblolly pine wood stakes in the mineral soil of plots receiving the bole only harvesting treatment (BO) and the whole tree harvesting with forest floor removal treatment (WT + FF), and in plots in an adjacent unharvested reference area (1350 wood stakes total). Soil was also sampled to characterize the microbial community composition in the various treatments. From 2014 to 2018, wood stakes were removed from each treatment, and mass loss determined. We found significant differences in wood stake decomposition among the three sites, and between the two wood species, but little impact of timber harvesting and surface OM removals on decomposition. Soil microbial composition also reflected site differences in stake decomposition. We conclude that clearcut harvest and surface OM removal had little effect on stake mass loss in the mineral soil 20 years after the treatments were initiated, and the inherent soil factors are now controlling decomposition.