|Year||Title (Author, Description)||File Download|
Leverage Points: Places to intervene in a system
Donella H. Meadows
What you are about to read is a work in progress. It's not a simple, sure-fire recipe for finding leverage points. Rather, it's an invitation to think more broadly about the many ways there might be to get systems to change.
|Contact ALCES for Donella H. Meadows, 1999|
Soil Carbon Sequestration and Land-Use Change: Processes and Potential
W. M. Post, and K. C. Kwon
When agricultural land is no longer used for cultivation and allowed to revert to natural vegetation or replanted to perennial vegetation, soil organic carbon can accumulate by processes that essentially reverse some of the effects responsible for soil organic carbon losses from when the land was converted from perennial vegetation.We discuss the essential elements of what is known about soil organic matter dynamics that may result in enhanced soil carbon sequestration with changes in land-use and soil management.We review literature that reports changes in soil organic carbon after changes in land-use that favor carbon accumulation. This data summary provides a guide to approximate rates of SOC sequestration that are possible with management, and indicates the relative importance of some factors that influence the rates of organic carbon sequestration in soil. There is a large amount of variation in rates and the length of time that carbon may accumulate in soil that are related to the productivity of the recovering vegetation, physical and biological conditions in the soil, and the past history of soil organic carbon inputs and physical disturbance. Maximum rates of C accumulation during the early aggrading stage of perennial vegetation growth, while substantial, are usually much less than 100 g C m y . Average rates of accumulation are similar for forest or grassland establishment: 33.8 g C m y and 33.2 g C m y respectively. These observed rates of soil organic C accumulation, when combined with the small amount of land area involved, are insufficient to account for a significant fraction of the missing C in the global carbon cycle as accumulating in the soils of formerly agricultural land.
|Contact ALCES for W. M. Post, and K. C. Kwon, 1999|
A Method for Measuring Sediment Production from Forest Roads
Predicting sediment production from forest roads is necessary to determine their impact on watersheds and associated terrestrial and stream biota. A method is presented for measuring sediment originating from a road segment for individual storm events and quantifying the delivery to streams. Site selection criteria are listed to describe the characteristics for efficient data collection and analysis. The method describes equipment used to quantify sediment transport—data loggers, a rain gage, a traffic counter, Parshall flumes with stilling wells, hydrostatic pressure transducers, and water pumping samplers—as well as variables associated with sediment production—road surfacing material, traffic intensity, gradient, age, construction method, and precipitation. A sampling protocol that worked well for the forest roads in southeast Alaska and can be adapted for use in other regions also is described. Examples of data collection and analysis are explained both for sites near the road and downstream sites for sediment delivery quantification. This method can be used to determine the downstream transport of sediment originating from roads and developing regression models or validating existing sediment models.
|Contact ALCES for Keith Kahklen, 2001|
Forecast of Common Air Contaminants in Alberta (1995 to 2020)
Cheminfo Services Inc.
The main focus of this report is on the growth in anthropogenic emissions from industrial sources in Alberta. Large natural sources are documented and included in the total emissions, but in the forecast period from 1995 to 2020, these are kept constant at 1995 levels. These sources are highly variable from year to year such that any analysis regarding how they may change due to natural causes (e.g., lightning for forest fires, precipitation, temperatures, etc.) requires further detailed research and customized modelling beyond the scope of this project. By keeping emissions from natural sources constant, it focuses the analysis of changes in CAC emissions on anthropogenic sources. The inclusion of natural sources provides perspective on the relative contribution to total CAC air emissions and can be useful for regional ambient air quality modelling using the results of this analysis.
|Contact ALCES for Cheminfo Services Inc., 2002|
Quantifying barrier effects of roads and seismic lines on movements of female woodland caribou in northeastern Alberta
Simon J. Dyer, Jack P. O’Neill, Shawn M. Wasel, and Stan Boutin
Linear developments such as roads, seismic lines, and pipeline rights-of-way are common anthropogenic features in the boreal forest of Alberta. These features may act as barriers to the movement of threatened woodland caribou (Rangifer tarandus caribou). Thirty-six woodland caribou were captured and fitted with global positioning system collars. These collared caribou yielded 43 415 locations during the 12-month study period. We compared rates of crossing roads and seismic lines with rates at which caribou crossed simulated roads and seismic lines created using ArcInfo GIS. Seismic lines were not barriers to caribou movements, whereas roads with moderate vehicle traffic acted as semipermeable barriers to caribou movements. The greatest barrier effects were evident during late winter, when caribou crossed actual roads 6 times less frequently than simulated road networks. Semipermeable barrier effects may exacerbate functional habitat loss demonstrated through avoidance behaviour. This novel approach represents an important development in the burgeoning field of road ecology and has great potential for use in validating animal-movement models.
|Contact ALCES for Simon J. Dyer, Jack P. O’Neill, Shawn M. Wasel, and Stan Boutin, 2002|
Development of a Threshold Approach for Assessing Industrial Impacts on Woodland Caribou in Yukon
Robert B. Anderson, M.Sc., P.Biol., R.B.Bio. Simon J. Dyer, M.Sc., P.Biol. Shawn R. Francis, M.Sc.,
To date, no jurisdiction in Canada has established, implemented and enforced cumulative effects thresholds for industrial activity in woodland caribou range. Instead, guidelines and regulations have been put in place in an attempt to minimize and mitigate the impacts of individual development projects on caribou. Under this system of management, many caribou populations throughout the provinces are either the focus of concern or have been extirpated from former ranges. In some situations, caribou ranges have already been severely impacted and will require a great deal of effort, financial resources, and political will to return habitat effectiveness to an acceptable level. Yukon has a unique opportunity to develop and implement cumulative effects thresholds for caribou range prior to large-scale industrial development over significant areas. This must be initiated now if Yukon wishes to have healthy caribou populations in perpetuity. The current report is intended to assess potential threshold approaches and recommend a methodology for setting industrial thresholds for woodland caribou range in Yukon. The criteria for recommending a threshold development strategy was that it: 1) be directly relevant to caribou ecology, 2) truly assess cumulative effects of known human influences on caribou, 3) be able to suggest a clear threshold, and 4) be usable and acceptable by a wide range of stakeholders. Based on a literature review, experience from other jurisdictions, and consideration of the Yukon situation, it was concluded that the most appropriate method for developing cumulative effects thresholds for Yukon caribou range was the habitat effectiveness approach, whether it be based on a full habitat effectiveness model or simply a total zone of influence. This approach addresses the influence of industrial activity on caribou ecology, includes cumulative effects from several disturbance types, can be related to clear thresholds, and generally meets the criteria of being usable and acceptable by a wide range of stakeholders. Although habitat effectiveness calculations incorporate, in a general sense, the importance of human features in changing mortality rates due to humans and other predators, and the effects of spatial distribution of harvest on caribou habitat effectiveness, there are obvious limitations to this relatively simple threshold approach. Range-specific factors, such as predator density, or distance to human settlements, may influence caribou recruitment and survival differently, despite ranges having similar habitat effectiveness values. Despite these limitations, setting of thresholds represents a risk management exercise for development of industrial activity in caribou range, and is a more defensible management technique than the alternative approaches (projectspecific mitigation strategies), which have largely failed in other jurisdictions Most elements required for the development and implementation of the habitat effectiveness approach within Yukon already exist. The data required to set a threshold for Yukon caribou range are either already in existence, or could be acquired in a timely fashion. The technical expertise and technological resources required to implement thresholds currently exist in Yukon and are fully capable of developing the tools needed to assess proposed projects and undertake long-term range planning. The coordination of these activities among government agencies and existing management structures will be the greatest challenge to implementing a threshold approach for Yukon.
|Contact ALCES for Robert B. Anderson, M.Sc., P.Biol., R.B.Bio. Simon J. Dyer, M.Sc., P.Biol. Shawn R. Francis, M.Sc., , 2002|
Ecological basis for stand management: A synthesis of ecological responses to wildfire and harvesting
Samantha Song (editor)
Public concern over the ecological impacts of clearcutting and loss of old growth forest, as well as the increased knowledge of natural disturbance dynamics of forests, has prompted a number of agencies in North America to re-evaluate forest practices. Increasingly, in an attempt to address these concerns, many government departments and corporations have released new policies and guidelines to supplement or replace the current suite of harvesting practices with a broader range of approaches that are intended to use natural disturbance as a model. Generally, the intent of the natural disturbance template is that biotic systems adapted to natural disturbance may be better managed under a harvesting regime that attempts to emulate those disturbances rather than under existing clearcutting practices. This represents a different focus for altering harvest practices than models that aim to protect old forest seral stages, although there are many overlapping components. The objective of the Ecological Basis for Stand Management project was to review, synthesize, and evaluate the ecological basis for harvest practices at the stand level in boreal mixedwood forests. Our approach critically assessed two strategies for forest management: management for old growth seral stages, and management to emulate natural disturbances, particularly wildfire. Using a chronosequence approach and with some re-analysis of existing data, we reviewed the ecological effects of wildfires on forests, then compared with clearcutting and retention of residual trees. We compared ecological elements at each seral stage to old seral stage forests. We also documented existing information on biotic responses to riparian areas and forest edges.
|Contact ALCES for Samantha Song (editor), 2002|
Scenario Planning: a Tool for Conservation in an Uncertain World
Garry Peterson, Graeme Cumming, and Stephen Carpenter
Conservation decisions about how, when, and where to act are typically based on our expectations for the future. When the world is highly unpredictable and we are working from a limited range of expectations, however, our expectations will frequently be proved wrong. Scenario planning offers a framework for developing more resilient conservation policies when faced with uncontrollable, irreducible uncertainty. A scenario in this context is an account of a plausible future. Scenario planning consists of using a few contrasting scenarios to explore the uncertainty surrounding the future consequences of a decision. Ideally, scenarios should be constructed by a diverse group of people for a single, stated purpose. Scenario planning can incorporate a variety of quantitative and qualitative information in the decision-making process. Often, consideration of this diverse information in a systemic way leads to better decisions. Furthermore, the participation of a diverse group of people in a systemic process of collecting, discussing, and analyzing scenarios builds shared understanding. The robustness provided by the consideration of multiple possible futures has served several groups well; we present examples from business, government, and conservation planning that illustrate the value of scenario planning. For conservation, major benefits of using scenario planning are (1) increased understanding of key uncertainties, (2) incorporation of alternative perspectives into conservation planning, and (3) greater resilience of decisions to surprise.
|Contact ALCES for Garry Peterson, Graeme Cumming, and Stephen Carpenter, 2003|
Land Advocate: News for Canadians living with oil and gas production
A democratic voice for landowners and the land. An advocate for more 100,000 farmers, ranchers and landowners in Saskatchewan, Alberta and British Columbia. We'll separate the oil from the gas to give you the best and most informed perspective on what's right and what's wrong in the oil patch.
|Contact ALCES for Andrew Nikiforuk, 2003|
Habitat Management in the Yukon Winter Range of the Little Rancheria Caribou Herd
J.Z. Adamczewski, R.F. Florkiewicz and V. Loewen
Woodland caribou (Rangifer tarandus caribou) ranges have shrunk substantially across North America due to the complex effects of human-caused habitat changes. As a result, COSEWIC1 listed nearly all woodland caribou populations in Canada as either Threatened or of Special Concern in May 2002. The Little Rancheria Herd (LRH) of caribou, which numbered about 1,000 in 1999, has a lowland forested winter range with some merchantable pine and spruce stands just west of Watson Lake, Yukon. Timber harvest in this range has to date (2003) been limited but the potential for habitat fragmentation is high. In this report we develop a long-term approach to habitat management of the Yukon LRH winter range, based on the herd’s habitat use and ecology, together with studies and management of woodland caribou elsewhere. The direct and indirect effects of development on woodland caribou include: • loss of fragile, slow-growing lichens, the • primary caribou winter forage, • avoidance of disturbed areas, particularly those with heavy traffic, • increased hunter access and harvest, • collisions with vehicles, • increased access to remote caribou range for predators, primarily wolves, and • improved habitat suitability for other • ungulates like moose. Where these other prey sustain elevated wolf numbers, caribou numbers often decline. Alberta studies showed that caribou were more likely to be killed by wolves in areas within 250 m of all recent cut-blocks and other developments, and that caribou used these areas much less than undisturbed forests. The development “footprint” was defined as the proportion of the land-base within such avoidance zones. Where the development footprint in a caribou range was 50% or greater, the population was likely to be declining at 1–3% annually, even with little or no hunting. Threshold levels limiting the footprint in caribou range have been proposed as a management option for the Yukon. Management guidelines for caribou ranges in British Columbia and Ontario focus on protecting critical caribou habitat from development and access, and allow carefully managed development in less sensitive caribou range. Three management zones in the Yukon LRH winter range were identified in the 1990s based first on reconnaissance surveys and later confirmed by radio-collar locations: a heavily used core, a surrounding extended range, and a migration corridor. Although just 3.6% of the land-base had been cut for timber by 2002, the development footprint in the LRH Yukon winter range was 16% overall, with 18% in the core, 18% in the extended range, and 5% in the migration zone. Like most Yukon caribou herds, the LRH is hunted. The estimated annual harvest rate averaged 5% from 1992 to 2002. To enable continued hunting of this herd, and to allow for periodic range losses to fire, development in this winter range must be kept at levels well below the 50% footprint values linked to serious declines in Alberta. The suggested management approach for the LRH Yukon winter range is based on British Columbia models, Alberta studies, and recent reports proposing thresholds for development footprint in caribou range. The main points of the approach are: • withdraw the core winter range from further logging or development, • establish a connected reserve network of high-quality habitat in the extended range and migration zone, and • establish maximum development footprint values of 30% in the extended range and 25% in the migration zone.
|Contact ALCES for J.Z. Adamczewski, R.F. Florkiewicz and V. Loewen , 2003|