scholarly journals Natural disturbance regimes for implementation of ecological forestry: a review and case study from Nova Scotia, Canada

2021 ◽  
Author(s):  
David A. MacLean ◽  
Anthony R. Taylor ◽  
Peter D. Neily ◽  
James W. N. Steenberg ◽  
Sean P. Basquill ◽  
...  
Keyword(s):  
Nova Scotia ◽  
Natural Disturbance ◽  
Stand Age ◽  
Land Classification ◽  
Disturbance Regimes ◽  
High Severity ◽  
Ecological Land Classification ◽  
Novel Approach ◽  
Ecological Forestry ◽  
Patterns And Processes

Ecological forestry is based on the idea that forest patterns and processes are more likely to persist if harvest strategies produce stand structures, return intervals, and severities similar to those from natural disturbances. Taylor et al. (2020) reviewed forest natural disturbance regimes in Nova Scotia, Canada, to support implementation of ecological forestry. In this follow-up paper, we 1) review use of natural disturbance regimes to determine target harvest rotations, age structures, and residual stand structures; and 2) describe a novel approach for use of natural disturbance regimes in ecological forestry developed for Nova Scotia. Most examples of ecological forestry consider only the local, dominant disturbance agent, such as fire in boreal regions. Our approach included: 1) using current ecological land classification to map potential natural vegetation (PNV) community types; 2) determining cumulative natural disturbance effects of all major disturbances, in our case fire, hurricanes, windstorm, and insect outbreaks for each PNV; and 3) using natural disturbance regime parameters to derive guidelines for ecological forestry for each PNV. We analyzed disturbance occurrence and return intervals based on low, moderate, and high severity classes (<30, 30-60, and >60% of biomass of living trees killed), which were used to determine mean annual disturbance rates by severity class. Return intervals were used to infer target stand age-class distributions for high, moderate, and low severity disturbances for each PNV. The range of variation in rates of high severity disturbances among PNVs was from 0.28% yr-1 in Tolerant Hardwood to 2.1% yr-1 in the Highland Fir PNV, equating to return intervals of 357 years in Tolerant Hardwood to 48 yrs in Highland Fir PNVs. As an example, this return interval for the Tolerant Hardwood PNV resulted in target rotation lengths of 200 years for 35% of the PNV area, 500 years for 40%, and 1000 years for 25%. The proposed approach of determining natural disturbance regimes for PNV communities and calculating target disturbance rates and corresponding harvest rotation lengths or entry times appears to be a feasible method to guide ecological forestry in any region with a strong ecological land classification system and multiple disturbance agents.

scholarly journals A review of natural disturbances to inform implementation of ecological forestry in Nova Scotia, Canada

2020 ◽  
Vol 28 (4) ◽  
pp. 387-414
Author(s):  
Anthony R. Taylor ◽  
David A. MacLean ◽  
Peter D. Neily ◽  
Bruce Stewart ◽  
Eugene Quigley ◽  
...  
Keyword(s):  
Nova Scotia ◽  
Natural Disturbance ◽  
Spruce Budworm ◽  
Natural Disturbances ◽  
Disturbance Regime ◽  
Individual Tree ◽  
Return Interval ◽  
High Severity ◽  
Ecological Forestry ◽  
Wide Scale

Like many jurisdictions across North America, the province of Nova Scotia (NS) is faced with the challenge of restoring its forests to a more natural, presettlement state through implementation of ecological forestry. At the core of ecological forestry is the idea that natural forest structures and processes may be approximated by designing management practices that emulate natural disturbances. Successful natural disturbance emulation depends on fundamental knowledge of disturbance characteristics, including identification of specific disturbance agents, their spatial extent, severity, and return interval. To date, no comprehensive synthesis of existing data has been undertaken to document the natural disturbance regime of NS forests, limiting the application of natural disturbance emulation. Using over 300 years of documents and available data, we identified the main natural disturbance agents that affect NS forests and characterized their regimes. Overall, fire, wind (predominantly hurricanes), and outbreaks of spruce budworm (Choristoneura fumiferana (Clemens)) are the most important disturbance agents, causing substantial areas of low- (<30% mortality), moderate- (30%–60%), and high- (>60%) severity disturbance. While characterization of natural historic fire is challenging, due to past human ignitions and suppression, we estimated that the mean annual disturbance rate of moderate- to high-severity fire ranged between 0.17% and 0.4%·year−1 (return interval of 250–600 years), depending on ecosystem type. Hurricanes make landfall in NS, on average, every 7 years, resulting in wide-scale (>500 ha) forest damage. While hurricane track and damage severity vary widely among storms, the return interval of low- to high-severity damage is 700–1250 years (0.14%–0.08%·year−1). Conversely, the return interval of host-specific spruce budworm outbreaks is much shorter (<50 years) but more periodic, causing wide-scale, low- to high-severity damage to spruce–fir forests every 30–40 years. Further disturbance agents such as other insects (e.g., spruce beetle), diseases, ice storms, drought, and mammals can be locally important and (or) detrimental to individual tree species but contribute little to overall disturbance in NS. Climate change is expected to significantly alter the disturbance regime of NS, affecting current disturbances (e.g., increased fire) and driving the introduction of novel agents (e.g., hemlock wooly adelgid), and continued monitoring is needed to understand these changes.

The Common Denominator of Land Classification in Canada: an Ecological Approach to Mapping

1980 ◽  
Vol 56 (1) ◽  
pp. 19-20 ◽  
Author(s):  
J. S. Rowe
Keyword(s):  
Ecological Approach ◽  
Common Denominator ◽  
Land Classification ◽  
Ecological Land Classification ◽  
Common Basis ◽  
The Common

The cores and boundaries of land units are located by reference to relationships between climate, landform and biota in ecological land classification. This appeal to relationships, rather than to climate, or to geomorphology, or to soils, or to vegetation alone, provides the common basis for land classification.

Is the END (emulation of natural disturbance) a new beginning? A critical analysis of the use of fire regimes as the basis of forest ecosystem management with examples from the Canadian western Cordillera

2016 ◽  
Vol 24 (3) ◽  
pp. 233-243 ◽  
Author(s):  
Chris Stockdale ◽  
Mike Flannigan ◽  
Ellen Macdonald
Keyword(s):  
Forest Management ◽  
Ecosystem Management ◽  
Forest Structure ◽  
Fire Regime ◽  
Natural Disturbance ◽  
Fire Regimes ◽  
Disturbance Regime ◽  
Ecological Processes ◽  
High Severity ◽  
Management Actions

As our view of disturbances such as wildfire has shifted from prevention to recognizing their ecological necessity, so too forest management has evolved from timber-focused even-aged management to more holistic paradigms like ecosystem-based management. Emulation of natural disturbance (END) is a variant of ecosystem management that recognizes the importance of disturbance for maintaining ecological integrity. For END to be a successful model for forest management we need to describe disturbance regimes and implement management actions that emulate them, in turn achieving our objectives for forest structure and function. We review the different components of fire regimes (cause, frequency, extent, timing, and magnitude), we describe low-, mixed-, and high-severity fire regimes, and we discuss key issues related to describing these regimes. When characterizing fire regimes, different methods and spatial and temporal extents result in wide variation of estimates for different fire regime components. Comparing studies is difficult as few measure the same components; some methods are based on the assumption of a high-severity fire regime and are not suited to detecting mixed- or low-severity regimes, which are critical to END management, as this would affect retention in harvested areas. We outline some difficulties with using fire regimes as coarse filters for forest management, including (i) not fully understanding the interactions between fire and other disturbance agents, (ii) assuming that fire is strictly an exogenous disturbance agent that exerts top-down control of forest structure while ignoring numerous endogenous and bottom-up feedbacks on fire effects, and (iii) assuming by only replicating natural disturbance patterns we preserve ecological processes and vital ecosystem components. Even with a good understanding of a fire regime, we would still be challenged with choosing the temporal and spatial scope for the disturbance regime we are trying to emulate. We cannot yet define forest conditions that will arise from variations in disturbance regime; this then limits our ability to implement management actions that will achieve those conditions. We end by highlighting some important knowledge gaps about fire regimes and how the END model could be strengthened to achieve a more sustainable form of forest management.

THE FOREST HABITAT TYPES IN SOUTHEASTERN MANITOBA AND THEIR APPLICATION TO FOREST MANAGEMENT

1964 ◽  
Vol 42 (10) ◽  
pp. 1417-1444 ◽  
Author(s):  
D. Mueller-Dombois
Keyword(s):  
Soil Moisture ◽  
Forest Management ◽  
Sand Dunes ◽  
Land Classification ◽  
Habitat Types ◽  
Forest Habitat ◽  
Regional Environment ◽  
Nutrient Regime ◽  
Ecological Land Classification ◽  
Silvicultural Practices

A forest ecological land classification in southeastern Manitoba resulted in the description of 14 forest habitat types, including three subtypes. These are based on silviculturally significant differences of soil moisture and nutrient regime, which are interpreted through tangible features of the three ecosystem components: vegetation, soil, and landform. The types encompass the regional environment from the driest habitats on sand dunes to the wettest in low moor bogs and from the nutritionally poorest on siliceous sandy podzols to the richest on alluvial bottomlands.The classification is to serve as a basic framework for silvicultural practices in the area. Aspects of application to current forest management are discussed.

scholarly journals ¿Podemos estimar el impacto de las transformaciones del paisaje sobre la ecodiversidad?

FACENA ◽  
2008 ◽  
Vol 21 ◽  
pp. 37
Author(s):  
Juan José Neiff ◽  
Marcelo Rolón ◽  
Sylvina L. Casco
Keyword(s):  
Yerba Mate ◽  
Land Classification ◽  
Ecological Land Classification ◽  
Landsat 7

Se han propuesto distintos criterios para medir la diversidad a nivel local (alfa y beta diversidad) a nivel regional (gama diversidad) y también a nivel del paisaje (ecodiversidad). De todas estas aproximaciones a la complejidad biótica en los ecosistemas, la ecodiversidad permite conocer la disponibilidad y la conectividad entre hábitat y lograr una idea de la variabilidad espacial de los ecosistemas. Se presentan siete índices de ecodiversidad y se discute sus ventajas y desventajas para el análisis de paisajes muy disturbados. Se analizó el paisaje del Establecimiento Las Marías, en el NE de Corrientes, que tiene algo más de 30.000 ha, comprendiendo 12.000 ha de sistemas forestales nativos y cultivados y 18.000 ha. dedicadas a té, yerba mate y policultivos. Se utilizó imágenes Landsat 7 y el procedimiento de Ecological Land Classification (ELC), para identificar las principales unidades de paisaje (bosques, pasturas, cuerpos de agua, diferentes cultivos). Se encontraron tres subsistemas de paisaje diferentes, se obtuvo información del número de polígonos y de la superficie comprendida en cada uso del paisaje y se la comparó cuantitativamente mediante varios índices. Se concluye que una determinada unidad de paisaje puede tener muy diferente diversidad, según el contexto de paisaje en el que se encuentre incluida.

Silviculture that sustains: the nexus between silviculture, frequent prescribed fire, and conservation of biodiversity in longleaf pine forests of the southeastern United States

2006 ◽  
Vol 36 (11) ◽  
pp. 2724-2736 ◽  
Author(s):  
R J Mitchell ◽  
J K Hiers ◽  
J J O'Brien ◽  
S B Jack ◽  
R T Engstrom
Keyword(s):  
Prescribed Fire ◽  
Prescribed Burning ◽  
Longleaf Pine ◽  
Pinus Palustris ◽  
Natural Disturbance ◽  
Primary Objective ◽  
Growth And Yield ◽  
Key Factor ◽  
Patterns And Processes ◽  
Conservation Of Biodiversity

The longleaf pine (Pinus palustris Mill.) forest ecosystems of the US southeastern Coastal Plain, among the most biologically diverse ecosystems in North America, originally covered over 24 × 106 ha but now occupy less than 5% of their original extent. The key factor for sustaining their high levels of diversity is the frequent application of prescribed fire uninterrupted in time and space. Pine fuels, critical to application of fire and regulated by canopy distribution, provide the nexus between silviculture and fire management in this system. Typical silvicultural approaches for this type were, in large part, developed to maximize the establishment and growth of regeneration as well as growth and yield of timber, with much less regard to how those practices might influence the ability to sustain prescribed burning regimes or the associated biodiversity. However, many landholdings in the region now include conservation of biodiversity as a primary objective with sustained timber yield as an important but secondary goal. This review synthesizes the literature related to controls of biodiversity for longleaf pine ecosystems, and silvicultural approaches are compared in their ability to sustain natural disturbance such as fire and how closely they mimic the variation, patterns, and processes of natural disturbance regimes while allowing for regeneration.

Ecological land survey in Quebec

1992 ◽  
Vol 68 (1) ◽  
pp. 42-52 ◽  
Author(s):  
L. Bélanger ◽  
C. Camiré ◽  
Y. Bergeron
Keyword(s):  
Forest Ecology ◽  
Two Dimensions ◽  
Department Of Energy ◽  
Site Classification ◽  
Ecological Framework ◽  
Forest Site ◽  
Land Classification ◽  
Ecological Survey ◽  
The Past ◽  
Ecological Land Classification

After a brief review of floristic classifications, ecological survey, as carried out in Quebec, is described. Three stages of development of ecological survey over the past twenty-five years are identified: (1) the pioneer work of Jurdant; (2) major ecological surveys from the late 1960s to the late 1970s; and (3) the diversification of the groups involved in ecological land surveys beginning in the 1980s, including universities, the Quebec Environment Department (MENVIQ) and the Quebec Department of Energy and Resources (MER). Intended for use in integrated land management, ecological survey must be an effective integrator of the various ecological evaluations; the information must be easily communicable and the methodology must be flexible. Ecological land classification has two dimensions: (1) taxonomic; and (2) cartographic. In the taxonomic units, the ecological region, the ecological type and the ecological phase are identified. In cartographic terms, local (ecological phase and type), regional (ecological system and subsystem) and national (ecological district and region) resolution is identified.Quebec universities, MER and MENVIQ are presently involved in ecological land surveys. The new Forest Act, which was enacted in 1986 and which provides for sustainable yield and more intensive forest management, is a major force behind the promotion of the use of ecological inventories as the basis for management activities. Mapping of the ecological regions (1:1,250,000) has almost been completed in Quebec. Total coverage of the commercial forest as a function of ecological districts (1:250,000) could be completed within five years, and the mapping of ecological types (1:20,000) could be completed in 20 years at a rate of 10,000 km2 a year. Although in the past ecological land surveys have been used primarily for environmental impact analyses (for instance, the installation of hydroelectric equipment and transportation corridors), the ecological framework is presently being used to prepare development plans for a number of regional county municipalities (RCMs). Pilot projects are under way to assess the potential applications of the ecological framework to forestry as part of intensive management efforts. Improvements are needed in both the accessibility of the information provided by the ecological framework (maps, site guides) and the development of interpretative tools for silvicultural measures. Key words: ecological survey, ecosystem mapping, ecological land classification, forest ecology, forest site classification, Quebec.

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