Decadal soil and stand response to fire, harvest, and salvage-logging disturbances in the western boreal mixedwood forest of Alberta, Canada

2015 ◽  
Vol 45 (2) ◽  
pp. 141-152 ◽  
Author(s):  
B.E. Kishchuk ◽  
E. Thiffault ◽  
M. Lorente ◽  
S. Quideau ◽  
T. Keddy ◽  
...  
Keyword(s):  
Forest Floor ◽  
Management Practices ◽  
Exchange Capacity ◽  
First Year ◽  
Productive Capacity ◽  
Foliar Nutrition ◽  
Salvage Logging ◽  
Mixedwood Forests ◽  
Recovery Trajectory

Empirical knowledge of long-term ecosystem response to single and compound disturbances is essential for predicting disturbance effects and identifying management practices to maintain productive capacity of managed and restored landscapes. We report on soil, foliar nutrition, and regeneration growth response to wildfire, clearcut harvesting, and postfire salvage logging, as well as undisturbed control stands within the first year following disturbance and 10–11 years after disturbance in trembling aspen – white spruce mixedwood forests near Lesser Slave Lake, north-central Alberta, Canada. The compound disturbance of salvage logging resulted in greater long-term impacts on forest floor properties than either wildfire or harvesting alone. Changes in forest floor properties such as carbon and nitrogen pools and cation exchange capacity under salvage logging have persisted for 10 years and exhibit a different recovery trajectory than fire or harvesting. Forest floor properties under harvesting, including depth, carbon content, pH, extractable ammonium, and extractable sulphur, were not different from the control condition 10 years after harvest. Effects on soil and foliar nutrition were not reflected in productivity (height and diameter) of regenerating vegetation. Our results show differences between short- and long-term responses to disturbance, among single natural and anthropogenic disturbances, and among single and compound disturbances.

Ontario, Canada’s LTSP Experience: Forging Lasting Research Partnerships and the Adaptive Management Cycle in Action

2020 ◽  
Vol 118 (3) ◽  
pp. 337-351
Author(s):  
Dave M Morris ◽  
Rob L Fleming ◽  
Paul W Hazlett
Keyword(s):  
Adaptive Management ◽  
Management Practices ◽  
Forest Policy ◽  
Lessons Learned ◽  
Soil Productivity ◽  
Research Partnerships ◽  
Foliar Nutrition ◽  
Individual Tree ◽  
The North

Abstract In this paper, we summarize Ontario’s Long-term Soil Productivity (LTSP) experience focusing on our efforts to forge lasting research partnerships, highlight the approaches we feel were effective in getting emerging science into forest policy within an adaptive management (AM) framework, and describe the future direction of Ontario’s LTSP program as new policy issues are emerging as part of the continuous AM cycle. Fourteen installations were established on nutrient-poor, conifer-dominated sites, considered to be the most sensitive to increased biomass removals. From 1993 to 1995, all sites were clearcut-harvested, with replicated (three reps per site) biomass removal treatments that included: stem only, full-tree, and full-tree + forest floor removal. Routine (every 5 years) measurements have been carried out to track changes in soil carbon and nutrient levels, as well as stand- and individual-tree growth and development metrics and foliar nutrition. The published results from Ontario’s LTSP program, in combination with the North American-wide LTSP synthesis outputs, have suggested that these nutrient-poor, conifer-dominated sites are less sensitive to biomass (nutrient) removals than previously thought. The evidence provided through peer-reviewed publications, conference and workshop presentations, and field tours was substantive and led to a review and revision of the full-tree logging direction within Ontario’s guidelines. We conclude with a set of recommendations (lessons learned) for the successful delivery of any new long-term, interdisciplinary research projects examining the sustainability of forest-management practices.

Long-term recovery in the soil profile of 15N from Douglas-fir needles decomposing in the forest floor

1995 ◽  
Vol 25 (5) ◽  
pp. 833-837 ◽  
Author(s):  
CM. Preston ◽  
D.J. Mead
Keyword(s):  
Soil Profile ◽  
Forest Floor ◽  
Mineral Soil ◽  
Sampling Period ◽  
Douglas Fir ◽  
First Year ◽  
N Recovery ◽  
Inorganic N ◽  
Almost All

To follow the movement and transformations of litter-fall N in a forest ecosystem, Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) foliage labelled with 15N was mixed into the forest floor and left to decompose in steel cylinders of 15 cm diameter X 60 cm length. There were four treatments: 15N-labelled foliage only, foliage plus 200 kg N•ha−1 as urea or NH4NO3, and unamended control. The addition of fertilizer N had no significant effects on 15N recovery or distribution in the soil profile. The overall recovery of 15N to 60 cm depth was 53.7%, 24.9%, and 19.9% after 1, 3, and 7.5 years, respectively. After the first year almost all of the recovered 15N was in the L layer. At 3 years, a higher proportion was found in the FH layer, and by 7.5 years, approximately one-third of the 15N was found in mineral soil horizons. There was very little recovery of 15N in inorganic form (1% or less) after 1 year; in subsequent years inorganic N was found at background levels. Recoveries in soil after 1 and 3 years were similar to those reported for 15N added as inorganic fertilizer in the absence of plant uptake. However, very low losses in the next sampling period (3 to 7.5 years) indicated stabilization of 15N in increasingly recalcitrant forms.

scholarly journals Hydrologic Impacts of Logging an Appalachian Watershed Using West Virginia's Best Management Practices

1997 ◽  
Vol 14 (4) ◽  
pp. 207-218 ◽  
Author(s):  
James N. Kochenderfer ◽  
Pamela J. Edwards ◽  
Frederica Wood
Keyword(s):  
Best Management Practices ◽  
Management Practices ◽  
Basal Area ◽  
Growing Season ◽  
First Year ◽  
Best Management ◽  
Hydrologic Impacts ◽  
Dormant Season ◽  
Understory Shrubs

Abstract A 39 ha gauged watershed located in north-central West Virginia near Parsons was cut to a 35.5 cm stump diameter and logged using wheeled skidders to evaluate the effectiveness of West Virginia's Best Management Practices (BMPs). Roads initially occupied 10.6% of the watershed, but this percentage is decreasing as much of the original road prism reverts to forest. Reducing basal area by 44% in stems 2.54 cm dbh and larger had a negligible effect on maximum growing season stream temperatures, apparently because the stream remained shaded by residual trees and understory shrubs growing along it. Both growing season peakflows and total stormflow had small but significant increases due to treatment. Dormant season stormflows did not increase significantly. Although mean monthly exports of suspended sediment doubled the first year when the area was being logged, they remained within the range reported for carefully managed areas in the East. Sediment exports returned to pretreatment levels by the third posttreatment year. Long-term projections of current exports rates indicate that sediment exports from harvesting operations (3 entries) during a 100 yr rotation will account for less than 5% of the total sediment exported from the study watershed. Nitrate exports increased significantly during most of the monitored posttreatment years, but fertilizer applied to the roads during grass seeding is believed to have contributed to these increases. Actual concentration values remained low, with maximum concentrations well below standards for potable water. Calcium concentrations also increased during most years, but road liming during seeding probably was responsible for most of this increase. The BMPs used in this study were effective in minimizing adverse impacts to soil and water resources. North. J. Appl. For. 14(4):207-218.

Changes in microbial biomass and organic matter levels during the first year of modified tillage and stubble management practices on a red earth

Soil Research ◽  
1994 ◽  
Vol 32 (6) ◽  
pp. 1339 ◽  
Author(s):  
V Gupta ◽  
MM Roper ◽  
JA Kirkegaard ◽  
JF Angus
Keyword(s):  
Organic Matter ◽  
Microbial Biomass ◽  
Microbial Activity ◽  
Management Practices ◽  
Microbial Respiration ◽  
Microbial Biomass C ◽  
First Year ◽  
Tillage Practices ◽  
Red Earth

Farming practices involving stubble burning and excessive tillage in Australia have led to losses of organic matter from the soil. Crop residue retention and reduced tillage practices can reverse these trends, but changes in organic matter levels are evident only after a long term. Microbial biomass (MB), the living portion of soil organic matter, responds rapidly to changes in soil and crop management practices. We evaluated changes in microbial biomass and microbial activity in the first year following the modification of stubble management and tillage practices on a red earth near Harden, New South Wales. Following an oat crop harvested late in 1989, seven treatments involving stubble and tillage management were applied in February 1990. Wheat was planted in May 1990. Measurements of total organic carbon (C) and total nitrogen (N) in the top 15 cm of soil indicated no significant changes after 1 year, although there was a significant effect on the distribution of C and N. However, significant changes in MB were observed in the first year. Microbial biomass C in the top 5 cm of the soil ranged from 25 to 52 g C m-2 and these levels dropped by 50% or more with each 5 cm depth. Implementation of treatments altered MB, particularly in the top 5 cm where MB-C and MB-N were significantly greater in stubble-retained than in the top 5 cm where MB-C and MB-N were significantly greater in stubble-retained than in the stubble-burnt treatments, and in the direct drill treatment than in the stubble-incorporated treatment. Microbial biomass in soil increased during the growth of wheat in all treatments, but this was slower in the standing stubble-direct drill treatment, probably due to the delay in the decomposition of stubble. Microbial respiration, which was concentrated in the surface 5 cm of soil in all treatments, was greatest in the direct drill treatments. Microbial activity below 5 cm was higher with stubble incorporation than with direct drill. Specific microbial activity (microbial respiration per unit MB) had the greatest response to tillage at 10-15 cm depth. Microbial quotients (MB as a percentage of C or N) responded to changes in tillage but not significantly to stubble retention. Our studies, during the first year following the modification of stubble management and tillage practices, suggested that changes in MB and microbial activity may be sensitive and reliable indicators of long-term changes in organic matter in soils.

CARDIOLOGICAL PROBLEMS IN THE LONG-TERM PERIOD IN CHILDREN AFTER AORTIC COARCTATION SURGERY TREATMENT IN THE FIRST YEAR OF LIFE

2018 ◽  
Vol 97 (3) ◽  
pp. 24-28
Author(s):  
M.R. Tumanyan ◽  
◽  
A.A. Svobodov ◽  
E.G. Levchenko ◽  
A.G. Anderson ◽  
...  
Keyword(s):  
Aortic Coarctation ◽  
First Year ◽  
First Year Of Life

Muenke syndrome: long-term outcome of a syndrome-specific treatment protocol

2019 ◽  
Vol 24 (4) ◽  
pp. 415-422 ◽  
Author(s):  
Bianca K. den Ottelander ◽  
Robbin de Goederen ◽  
Marie-Lise C. van Veelen ◽  
Stephanie D. C. van de Beeten ◽  
Maarten H. Lequin ◽  
...  
Keyword(s):  
Treatment Protocol ◽  
First Year ◽  
Ventricular Size ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Skull Growth ◽  
Muenke Syndrome ◽  
First Year Of Life

OBJECTIVEThe authors evaluated the long-term outcome of their treatment protocol for Muenke syndrome, which includes a single craniofacial procedure.METHODSThis was a prospective observational cohort study of Muenke syndrome patients who underwent surgery for craniosynostosis within the first year of life. Symptoms and determinants of intracranial hypertension were evaluated by longitudinal monitoring of the presence of papilledema (fundoscopy), obstructive sleep apnea (OSA; with polysomnography), cerebellar tonsillar herniation (MRI studies), ventricular size (MRI and CT studies), and skull growth (occipital frontal head circumference [OFC]). Other evaluated factors included hearing, speech, and ophthalmological outcomes.RESULTSThe study included 38 patients; 36 patients underwent fronto-supraorbital advancement. The median age at last follow-up was 13.2 years (range 1.3–24.4 years). Three patients had papilledema, which was related to ophthalmological disorders in 2 patients. Three patients had mild OSA. Three patients had a Chiari I malformation, and tonsillar descent < 5 mm was present in 6 patients. Tonsillar position was unrelated to papilledema, ventricular size, or restricted skull growth. Ten patients had ventriculomegaly, and the OFC growth curve deflected in 3 patients. Twenty-two patients had hearing loss. Refraction anomalies were diagnosed in 14/15 patients measured at ≥ 8 years of age.CONCLUSIONSPatients with Muenke syndrome treated with a single fronto-supraorbital advancement in their first year of life rarely develop signs of intracranial hypertension, in accordance with the very low prevalence of its causative factors (OSA, hydrocephalus, and restricted skull growth). This illustrates that there is no need for a routine second craniofacial procedure. Patient follow-up should focus on visual assessment and speech and hearing outcomes.

Engineering for good: A case of community driven engineering innovation

2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Chinweike Eseonu ◽  
Martin A Cortes
Keyword(s):  
Engineering Students ◽  
Technology Innovation ◽  
Local Communities ◽  
First Year ◽  
Engineering Curriculum ◽  
Engineering Design Process ◽  
The World ◽  
The University ◽  
Social Consideration

There is a culture of disengagement from social consideration in engineering disciplines. This means that first year engineering students, who arrive planning to change the world through engineering, lose this passion as they progress through the engineering curriculum. The community driven technology innovation and investment program described in this paper is an attempt to reverse this trend by fusing community engagement with the normal engineering design process. This approach differs from existing project or trip based approaches – outreach – because the focus is on local communities with which the university team forms a long-term partnership through weekly in-person meetings and community driven problem statements – engagement.

Monitoring Effects of Catchment Management Practices on Phosphorus Loads into the Eutrophic Peel-Harvey Estuary, Western Australia

1986 ◽  
Vol 18 (4-5) ◽  
pp. 53-61 ◽  
Author(s):  
P. B. Birch ◽  
G. G. Forbes ◽  
N. J. Schofield
Keyword(s):  
Management Practices ◽  
Major Change ◽  
High Flow ◽  
Catchment Management ◽  
Flow Rates ◽  
Early Results ◽  
Phosphorus Loads ◽  
Time Of Year ◽  
High Runoff

Early results from monitoring runoff suggest that the programme to reduce application of superphosphate to farmlands in surrounding catchments has been successful in reducing input of phosphorus to the eutrophic Peel-Harvey estuary. In the estuary this phosphorus fertilizes algae which grow in abundance and accumulate and pollute once clean beaches. The success of the programme has been judged from application of an empirical statistical model, which was derived from 6 years of data from the Harvey Estuary catchment prior to a major change in fertilizer practices in 1984. The model relates concentration of phosphorus with rate of flow and time of year. High phosphorus concentrations were associated with high flow rates and with flows early in the high runoff season (May-July). The model predicted that the distribution of flows in 1984 should have resulted in a flow-weighted concentration of phosphorus near the long-term average; the observed concentration was 25% below the long-term average. This means that the amount of phosphorus discharged into the Harvey Estuary could have been about 2 5% less than expected from the volume of runoff which occurred. However several more years of data are required to confirm this trend.

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